Search results for "Bottom"

showing 10 items of 450 documents

Enhancing Sensitivity of Microflow-Based Bottom-Up Proteomics through Postcolumn Solvent Addition.

2019

The introduction of more sensitive mass spectrometers allows researchers to adapt front-end liquid chromatography (LC) to individual needs for the analysis of complex proteomes. Where absolute sensitivity is not paramount, it is advantageous to switch from a highly sensitive nanoflow-LC setup, the de facto standard platform in mass-spectrometry (MS)-based discovery proteomics, to a more robust, high-throughput-compatible microflow or conventional-flow setup. To enhance the microflow-LC-MS electrospray process of complex proteomic samples, we tested the effects of different solvents, including 2-propanol, methanol, and acetonitrile, pure or as mixture with dimethyl sulfoxide, which were adde…

ProteomicsElectrospraySpectrometry Mass Electrospray IonizationChromatographyChemistryDimethyl sulfoxideElectrospray ionization010401 analytical chemistry010402 general chemistryMass spectrometry01 natural sciences0104 chemical sciencesAnalytical ChemistrySolventchemistry.chemical_compoundSolventsHumansNanotechnologyDimethyl SulfoxideBottom-up proteomicsMethanolAcetonitrilePeptidesChromatography High Pressure LiquidHeLa CellsAnalytical chemistry
researchProduct

Hybrid QconCAT-Based Targeted Absolute and Data-Independent Acquisition-Based Label-Free Quantification Enables In-Depth Proteomic Characterization o…

2021

Wheat amylase/trypsin inhibitors (ATIs) have gained significant relevance as inducers of intestinal and extra-intestinal inflammation. In this study, we present a novel hybrid data-independent acquisition (DIA) liquid chromatography-mass spectrometry (LC-MS) approach, combining QconCAT technology with short microflow LC gradients and DIA and apply the method toward the quantitative proteome analysis of ATI extracts. The presented method is fast, robust, and reproducible and provides precise QconCAT-based absolute quantification of major ATI proteins while simultaneously quantifying the proteome by label-free quantification (LFQ). We analyzed extracts of 60 varieties of common wheat grown in…

ProteomicsPlant ExtractsTrypsin inhibitorReproducibility of ResultsContext (language use)General ChemistryComputational biologyBiologyBiochemistryPlant BreedingLabel-free quantificationAmylasesProteomebiology.proteinTrypsinData-independent acquisitionBottom-up proteomicsAmylaseCommon wheatTrypsin InhibitorsTriticumJournal of Proteome Research
researchProduct

Conflicting coccolithophore and geochemical evidence for productivity levels in the Eastern Mediterranean sapropel S1

2011

Abstract The cyclic development of anoxic conditions in the eastern Mediterranean deep sea waters is one of the most fascinating research topics in paleoceanographic studies. In combination with bottom water stagnation, enhanced primary production is a common explanation for the deposition of organic-rich layers (sapropels). This is supported by extensive evidence from both geochemical and micropaleontological studies. The correspondence of recent sapropel layers with peaks of the lower photic zone coccolithophore species Florisphaera profunda has been interpreted as a proxy for the development of a deep chlorophyll maximum (DCM), due to the pycnocline/nutricline shallowing into the lower p…

Pycnocline010504 meteorology & atmospheric sciencesCoccolithophoretrace elementsNannofossil Accumulation Rates Trace Elements Sapropel S1 Deep Chlorophyll Maximum010502 geochemistry & geophysicsOceanography01 natural sciencesDeep seaCoccolithBottom waterEastern Mediterranean SeaPhotic zone14. Life underwaterNannofossil Accumulation Rates0105 earth and related environmental sciencesDeep chlorophyll maximumbiologyPaleontologySapropeldeep chlorophyll maximum15. Life on landbiology.organism_classificationsapropel S1OceanographyGeologyMarine Micropaleontology
researchProduct

"Table 2" of "Measurement of the correlations between the polar angles of leptons from top quark decays in the helicity basis at $\sqrt{s}=7$TeV usin…

2017

The correlation factors for the statistical uncertainties between any two bins of the unfolded distribution.

Quantitative Biology::BiomoleculesP P --> LEPTON+ NU LEPTON- NUBAR BOTTOM BOTTOMBAR XDifferential Cross SectionP P --> W+ W- BOTTOM BOTTOMBAR XTopTop Production7000.0Astrophysics::Cosmology and Extragalactic AstrophysicsPhysics::Data Analysis; Statistics and ProbabilityP P --> TOP TOPBAR XInclusiveProton-Proton ScatteringW Pair ProductionAngular DependenceW ProductionDSIG/DTHETA
researchProduct

"Table 1" of "Measurement of the correlations between the polar angles of leptons from top quark decays in the helicity basis at $\sqrt{s}=7$TeV usin…

2017

The numerical summary of the unfolded $\cos\theta_1\cdot\cos\theta_2$ distribution, with statistical and systematic uncertainties.

Quantitative Biology::BiomoleculesStatistics::TheoryP P --> LEPTON+ NU LEPTON- NUBAR BOTTOM BOTTOMBAR XDifferential Cross SectionMathematics::History and OverviewP P --> W+ W- BOTTOM BOTTOMBAR XTopTop Production7000.0P P --> TOP TOPBAR XInclusiveProton-Proton ScatteringW Pair ProductionAngular DependenceW ProductionDSIG/DTHETA
researchProduct

The b-quark mass from non-perturbative Nf=2 Heavy Quark Effective Theory at O(1/mh)

2014

Abstract We report our final estimate of the b-quark mass from N f = 2 lattice QCD simulations using Heavy Quark Effective Theory non-perturbatively matched to QCD at O ( 1 / m h ) . Treating systematic and statistical errors in a conservative manner, we obtain m ¯ b MS ¯ ( 2 GeV ) = 4.88 ( 15 ) GeV after an extrapolation to the physical point.

Quantum chromodynamicsPhysicsNuclear and High Energy PhysicsParticle physicsConservation lawHigh Energy Physics::LatticeHigh Energy Physics::PhenomenologyLattice field theoryExtrapolationLattice QCDBottom quarkNuclear physicsHeavy quark effective theoryHigh Energy Physics::ExperimentNon-perturbativePhysics Letters B
researchProduct

Charm and bottom quark masses from QCD moment sum rules

2002

In this work the charm and bottom quark masses are determined from QCD moment sum rules for the charmonium and upsilon systems. In our analysis we include both the results from non-relativistic QCD and perturbation theory at next-next-to-leading order. For the pole masses we obtain $M_c=1.75\pm 0.15$ GeV and $M_b=4.98\pm 0.125$ GeV. Using the potential-subtracted mass in intermediate steps of the calculation the MS-masses are determined to $m_c(m_c) = 1.19 \pm 0.11$ GeV and $m_b(m_b) = 4.24 \pm 0.10$ GeV.

Quantum chromodynamicsPhysicsNuclear and High Energy PhysicsParticle physicsHigh Energy Physics::LatticeHigh Energy Physics::PhenomenologyOrder (ring theory)FOS: Physical sciencesBottom quarkAtomic and Molecular Physics and OpticsHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Moment (physics)B mesonHigh Energy Physics::ExperimentCharm (quantum number)Perturbation theory (quantum mechanics)Astrophysics::Earth and Planetary AstrophysicsNuclear Experiment
researchProduct

Bottom-quark mass from finite energy QCD sum rules

2011

Finite energy QCD sum rules involving both inverse and positive moment integration kernels are employed to determine the bottom quark mass. The result obtained in the $\bar{\text {MS}}$ scheme at a reference scale of $10\, {GeV}$ is $\bar{m}_b(10\,\text{GeV})= 3623(9)\,\text{MeV}$. This value translates into a scale invariant mass $\bar{m}_b(\bar{m}_b) = 4171 (9)\, {MeV}$. This result has the lowest total uncertainty of any method, and is less sensitive to a number of systematic uncertainties that affect other QCD sum rule determinations.

Quantum chromodynamicsPhysicsNuclear and High Energy PhysicsParticle physicsQCD sum rulesHigh Energy Physics - Lattice (hep-lat)High Energy Physics::PhenomenologyInverseFísicaFOS: Physical sciencesComputer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing)Bottom quarkHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)High Energy Physics - LatticeHigh Energy Physics::ExperimentSum rule in quantum mechanicsEnergy (signal processing)
researchProduct

B and B(S) decay constants from moments of finite energy sum rules in QCD

2004

We use an appropriate combination of moments of finite energy sum rules in QCD in order to compute the B_q-meson decays constants f_B and f_{B_s}.We perform the calculation using a two-loop computation of the imaginary part of the pseudoscalar two point function in terms of the running bottom quark mass. The results are stable with the so called QCD duality threshold and they are in agreement with the estimates obtained from Borel transform QCD sum rules and lattice computations.

Quantum chromodynamicsPhysicsParticle physicsQCD sum rulesPhysics and Astronomy (miscellaneous)High Energy Physics::LatticeHigh Energy Physics::PhenomenologyLattice (group)Duality (optimization)Order (ring theory)FOS: Physical sciencesFísicaBottom quarkPseudoscalarHigh Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)High Energy Physics::ExperimentEngineering (miscellaneous)Energy (signal processing)
researchProduct

Next-to-next-to-leading orderO(α2αs2)results for top quark pair production in photon-photon collisions: The one-loop squared contributions

2006

We calculate the one-loop squared contributions to the next-to-next-to-leading order ${\cal O}(\alpha^2\alpha_s^2)$ radiative QCD corrections for the production of heavy quark pairs in the collisions of unpolarized on--shell photons. In particular, we present analytical results for the squared matrix elements that correspond to the product of the one--loop amplitudes. All results of the perturbative calculation are given in the dimensional regularization scheme. These results represent the Abelian part of the corresponding gluon--induced next-to-next-to-leading order cross section for heavy quark pair hadroproduction.

Quantum chromodynamicsPhysicsQuarkNuclear and High Energy PhysicsParticle physicsTop quarkPhotonHigh Energy Physics::PhenomenologyOrder (ring theory)Bottom quarkNuclear physicsDimensional regularizationPair productionHigh Energy Physics::ExperimentPhysical Review D
researchProduct